Process of treating acid sludge



Patented June 19,

UNITED STATE ETE CHEMICAL COMPANY, OF WOBURN. IASSACEUSETTS, A CORPORATION OF HASSA cnosn'r'rs.

in Drawing. Application me Hey it,

To all whom it may com'cm:

Be it known that I, OSBORNE Bnzxn'soN, a citizen of the United States, residing at Woburn, in the county of Middlesexand State of Massachusetts, have invented certain new and useful Improvements 1n Processes of Treating Acid Sludge, of which the following is a specification.

This invention is a novel process for the utilization of the so-called acid sludge (or spent acid) derived as a by-product from the refining ofvarious petroleum fractions, such as gasoline, kerosene or the like, with sulfuric acid or fuming acid of any concentration or sulfuric anhydrid. The composition of the acid sludge resulting from such treatment of petroleum products necessarily varies over rather wide limits according to the nature of the petroleum and the particular methods of refining the same: it

consists essentially, however, of free sulfuric acid of va ing strength, sulfuric acid chemically comblned with tarry and other organic matters, and such oily residues as are physically retained by the acid sludge.

The disposal of this acid sludge and the most economical utilization of the same have been a subject of investigation for many years. Certain processes heretofore developed have not proven ecopomical m practice because of the large amount of fuel required in the operation. Another ob'ectionable feature common to man of t e pro posed processes is the unavoi able pollution as of the atm here by the extremely obnoxious odors w ich are liberated during the treatment of the sludge. Advantages characteristic of the present process are that very little or no auxiliary fuel is consumed,

40 and no objectionable odors are emitted at any point.

I have found that if acid sludge from the refining of petroleum is spra ed or atomized or otherwise injected in sub ivided as state into a suitable combustion chamber maintained at red heat or above (say from 500 C. upwards but referably around 700 C. or higher), comp ete decomposition occurs, and the sulfuric acid and other sulfur 60 compounds may be substantially completely converted into sulfur dioxid. is gas may be advantageously collected, or used in the manufacture of sulfuric acid or for any other purposes for which sulfur dioxid may be employed. The carbonaceous matter con- PROCESS OF TREATING ACID SLUDGE.

1821. Ee-rlal No. 469,814.

at the expense of the combmed oxygen in the sludge, and by air 'or oxygen admitted to the combustion chamber through the burner or otherwise. Sullicient heat is thereby produced to effect the decomposition of the existing sulfur compounds with formation of sulfur dioxid.

My process may be carried out either:

1. By spraying the acid sludge into a burner or furnace chamber of any of the well known types used for the combustion of sulfur, pyrites or other sulfur-bearin materials, the slud e being either sprayed directly upon or a ove the burning sulfur or into the combustion chamber or the furnace, or

2; By providing an independent combustion chamber equipped with an oil burner or other suitable means fior raising the chamber to red heat or above.

In the practice of the invention accordin to the second of the above mentioned em odiments, I 'have found that it is not necessary as a rule to employ auxiliary heat exce t for the purpose of bringing the combustion chamber up to the desired temperature, since. the combustion of the carbonaceous matter is contained in the acidsludge which is sprayed or atomized into the chamber develops therein sufiicient heat to easily maintain the temperature necessary for the complete decomposition of the acid sludge.

I claim 1. Process of treating acid sludge from the refining of petroleum, comprising injecting or spraying the same in subdivided state together with the necessary air into a chamber maintained at a sufiicient temperature to effect substantially complete decomposition of the sludge with liberation of its sulfur content as sulfur dioxid.

2. Process according to claim 1 in which the acid sludge is injected or sprayed into a burner in which pyrites, sulfur or other sulfur bearing materials may be combusted.

3. Process of treating acid sludge from the refining of petroleum, comprising injecting the same with the necessary air into a chamber maintained at a. temperature of at least red heat whereby odoriferous organic material in the sludge is destroyed and sulfur dioxid is produced, the heat nec- Q eeaoee essary for maintaining said combustion ficient temperature to efiect substantially 10 chamber at said temperature being derived complete decom osition of the sludge, wherefrom the combustion of the sludge. by sulfur dioxi containing gas suitable for 4. Process of treating acid sludge from use in the manufacture of sulfuric acid is 5 the refinin of petroleum which comprises produced.

injectin t e same with the necessary air In testimony whereof, I aflix my signa- 15 into a c amber in which pyrite, sulfur'er iure. other sulfur bearing material is bein burned, said chamber maintained at a su OSBORNE BlEZANSON.' 

